NASA software that thinks for itself and makes decisions
without help from ground controllers will fly as the brains of
triplet satellites in 2002.

The software builds on previous efforts to use artificial
intelligence to control a spacecraft (such as NASA's Remote
Agent experiment, which controlled the Deep Space 1 spacecraft
during portions of several days in 1999). However, this new
software uses more advanced technology to respond more quickly
to events and will command a mission continuously for a period
of approximately three months.

The Continuous Activity Scheduling, Planning Execution
and Replanning (CASPER) software will guide a constellation of
three identical miniature satellites, each weighing less than
15 kilograms (33 pounds). The three satellites will be
launched from the Space Shuttle in a stack configuration and
fly in formation as part of the Three Corner Sat mission.

"The onboard software performs the decision-making
function for the spacecraft. Like a brain that uses inputs
from the eyes and ears to make decisions, this software uses
data from spacecraft sensors, such as cameras, to make
decisions on how to carry out the mission," said Dr. Steve
Chien, principal scientist and lead researcher in automated
planning and scheduling technologies at NASA's Jet Propulsion
Laboratory, in Pasadena, Calif.

The mission goal is to demonstrate stereo imaging,
formation flying, and innovative operations and commanding.
The Three Corner Sat mission is a joint project of the
Arizona State University, the University of Colorado at Boulder,
New Mexico State University, the Air Force Office of
Scientific Research and NASA.

"Low-quality science images or short-lived phenomenon
could be discarded to free up space for newer science images.
The onboard sensors and software might detect a volcanic
eruption or solar flare might trigger science imaging," said
Chien.

The software is a dramatic shift in the way mission
operations are conducted. Typically all science data, good or
bad, is sent back to Earth. This software will have the
ability to make real-time decisions based on the images it
acquires and send back only those that it deems important.
This will eliminate the need for scientists to preview
thousands of low-priority images and let them focus on only
the high-priority data transmitted back. Less time will be
needed to transmit the data, freeing up power and allowing the
spacecraft to concentrate on other important tasks. Ground
controllers will have the ability to de-activate the onboard
decision-making software and operate the spacecraft
conventionally if necessary.

"This capability represents a significant advance from
traditional ground-based operations and offers promise to
dramatically increase mission science for this and future
missions," said Colette Wilklow, Three Corner Sat mission
operations team member and senior engineering major from the
University of Colorado.

The decision-making capability of the software is being
considered for a wide range of NASA applications including
automated ground communications stations, autonomous planetary
rovers and autonomous robot aircraft. Software with similar
capabilities has been used by commercial companies for
managing the distribution networks for groceries and other
retail goods and for controlling the production of computers,
automobiles, semiconductor chips, and consumer goods such as
shoes.

NASA's Office of Office of Space Science and Office of
Aerospace Technology, Washington, D.C., fund the development
of the CASPER software. JPL is managed for NASA by the
California Institute of Technology in Pasadena.